Module 5 : Peripheral Arterial System Part 1 Flashcards
14 risk factors for peripheral arterial disease
- diabetic
- hypertension
- hyperlipidemia
- coronary artery disease
- previous history of CVA or MI
- smoking
- age
- family history
- male
- obesity
- sedentary lifestyle
- elevated levels of homocysteine
- excessive levels of C-reactive protein
- history of radiation
Why diabetes is a risk factor for peripheral arterial disease
- atherosclerosis
- medial wall calcification common
- high incidence of gangrenous changes leading to amputation
what arteries have high incidence of occlusion with diabetes
- popliteal
- tibial
why is hypertension a risk for peripheral arterial disease
- increased incidence of peripheral and cerebral atherosclerosis
why is smoking a risk factor for peripheral arterial disease
- irritates endothelial lining and causes vasoconstriction
what are 4 physical signs of peripheral arterial disease
- skin changes
- palpations
- auscultations
- limb pressures
what are the 9 skin changes that can occur with peripheral arterial disease
- pallor
- rubor
- dependant rubor
- cyanosis
- temperature
- ulcers
- gangrene
- trophic changes
- capillary refill time
what is pallor
- pale color secondary to deficient blood supply
what is rubor
- dark reddish color or discolouration from dilated or damaged vessels
what is dependant rubor
- limb takes on pallor when elevated but becomes abnormally red when hanging dependant
what is cyanosis
- bluish color of the skin and mucous membranes that results from a concentration of deoxygenated hemoglobin
how does skin temperature change with peripheral arterial disease
- skin feels cool to the touch
what are ulcers
- deep, irregular shaped areas over the tibial area and are very painful
what is gangrene
- results from death of tissue form absent blood supply
what are trophic changes
- due to lack of nourishment
- shiny, scaly skin, thick toenails and loss of hair
what capillary refill time
- pressure is applied to an area of the skin and released
- color return should be immediate
- increase in this time indication of poor arterial supply
how to grade and check pulses
- graded from 0-4 where 0 is no pulse and 4 is a bounding pulse
- compare sides
- diminished or absent pulses suggest arterial insufficiency
what kind of pulse with an aneurysm have
- bounding pulses
what is a bruit
- abnormal low frequency sounds that can be caused by a significant stenosis graded from 1-3
- in a > 90% stenosis bruit is not heard
what does a difference in limb pressures indicate
- difference in pressures side to side may indicate disease or > 20 mmHg in upper and low extremity
what are 4 symptoms of peripheral arterial disease
- claudication (intermittent)
- ischemic rest pain
- necrosis
- pseudoclaudication
what is intermittent claudication
- muscle pain that occurs during exercise but subsides at rest
what is claudication caused by
- lack of blood supply to a group of muscles
is claudication reproducible
- yes
what are 4 common sites of claudication
- hip
- thigh
- butt
- calf
where is the site of disease relative to where the claudication occurs
- proximal
what does butt claudication suggest
- distal aortoiliac disease
what does which claudication suggest
- distal external iliac/CFA disease
what does calf claudication suggest
- femoral / popliteal disease
what is ischemic rest pain indicate
- always an indicator of advanced multisegment disease
- precursor to limb loss unless treated
what is the pain with ischemic rest pain
- severe and CONSTANT
what area is usually affected by ischemic rest pain
- dorm (top) of foot and toes
does rest relieve ascetic rest pain
- no
what is necrosis
- tissue death
- end stage of absent blood supply
what is the most severe symptom of ischemic rest pain
- necrosis
what is pseudoclaudication
- pain caused by other factors such such as degenerative joint disease, spinal stenosis, herniated discs
is pseudoclaudication reproducible
- no
what are 3 mechanisms of peripheral arteriole disease
- atherosclerosis
- embolism
- aneurysm
where is the most common location of atherosclerotic disease in the lower extremity
- SFA at the adductor canal
what are 2 other common sites of obstruction in lower extremity
- partial bifurcations
- popliteal artery
can atherosclerotic disease be focal or diffuse and what levels does it affect
- both
- may affect any level or multiple levels
how can an embolism causes disease
- from stenotic plaque formation
what is an aneurysm
- dilation of all walls of vessel
- may contain large amounts of thrombus
what are aneurysms usually due to
- trauma
- atherosclerosis
what are 3 common areas of aneurysm
- abdominal aorta AAA
- femoral
- popliteal artery
what are the two common areas of upper extremity aneurysms
- subclavian aneurysms
- ulnar aneurysms
what can subclavian aneurysms cause
- cause of embolization to distal arteries of the hand
what is most common cause of subclavian aneurysms
- result of compression of the subclavian artery due to THORACIC OUTLET SYNDROME
what are ulnar aneurysms caused by
- due to trauma from using hand as a hammer
- HYPOTHENAR HAMMER SNYDROME
what are 5 sonographic features of aneurysms
- increased diameter by > 50%
- image and measure in sag trans AP
- OUTER WALL TO OUTER WALL
- color doppler shows to and fro flow along outer wall
- measure actual lumen size if thrombus present
what are the 5 uses of duplex peripheral arterial testing
- determine STENOSIS OR OCCLUSION
- evaluate BYPASS GRAFTS
- presence or absence of ANEURYSMS
- locate stenotic lesions PRE SURGERY OR GRAFT
- FOLLOW UP
what are three limitations to duplex testing
- surface obstructions (dressings staples wounds)
- obesity
- Ca +++ in walls (arteriosclerosis)
11 indications for extremity duplex
- claudication
- rest pain
- extremity ulcer
- gangrene
- absent peripheral pulses
- digital cyanosis
- arterial trauma
- aneursymal disease
- abnormal ABI/WBI/TBI
- dependant rubor
- bruit
what is one specific indication for a lower extremity duplex exam
- decrease in ABI > 0.15 compared to previous exam
what are 5 specific indications for upper extremity duplex exam
- abnormal arterial arm pressures (>20mmHg)
- thoracic outlet symptoms
- prior to dialysis
- cold sensitivity
- raynauds syndrome
what do we look for in the 2D images in duplex exam
- vessel identification and lie of vessels
- assess walls for plaque
what doe we look for in the color imaging in duplex exams
- locate and follow vessels
- vessel patency (stenosis or occlusion)
- flow direction
- plaque
- placement of doppler sample
- grafts and bypass
- aneurysms
- follow up
what three things do we asses with pulsed doppler
- confrims patency of vessels
- quantifies flow speed
- waveform assessment
what arteries are assessed in LE duplex
- distal external iliac
- CFA
- CFA bifur
- SFA
- pop a
- trifurcation
what is the protocol in areas of suspected stenosis
- measure luminal reduction to help verify velocity data in hemodynamically significant stenosis
- obtain highest achievable velocity through any areas of stenosis
- obtain spectral information prox and distal to any stenosis
- MEASURE LUMEN REDUCTION IN GRAY SCALE
what vessels are assessed in upper extremity duplex exam
- subclavian (prox and dist)
- axillary
- brachial
- radial
- ulnar
- palmar arch if necessary
what is normal PSV of SCA and AXA
70-120 cm/s
what is normal PSV BrA
50-120cm/s
what is normal PSV of RA and UA
40-90cm/s
what should you do with the sample volume when stenosis is discovered
- walk the sample volume through the area to obtain representative velocities
+ 2cm prox, highest PSV, distal to stenosis
what 4 criteria should we determine in peripheral arterial disease
- plaque location and characteristics
- PSV and flow characteristics
- V2/V1 (V2 represents the max PSV and V1 PSV in normal)
- any change in spectral
what should normal gray scale and color look like in duplex exam
- no echoes seen within the lumen
- color doppler fills lumen wall to wall
what should normal doppler trace look like in normal LE duplex
- triphasic
- biphasic may be present without any visualized stenosis and may be considered normal
- abnormal would be change from tri to bi
are PSV uniform normal LE duplex
- yes
what is mean PSV in external iliac
120 +/- 22 cm/s
what is mean PSV in CFA
114 +/- 25 cm/sec
what is mean PSV in SFA prox
91 +/- 14 cm/s
what is mean PSV in SFA dist
94 +/- 14 cm/s
what is mean PSV in pop
69 +/- 13cm/s
what would gray scale and color look like in an abnormal LE duplex
- intraluminal echoes are sen and decreased lumen measures
- color doppler does not fill entire lumen and color jet seeing narrowed segment
- color mosaic see due to post stenotic turbulence
what would abnormal biphasic doppler signals look like in abnormal LE duplex testing
- strong forward flow in early systole (sharp upstroke)
- loss of flow in early diastole (non flow below baseline)
- decrease in late diastolic component
what would abnormal monophasic flow doppler signals look like in abnormal LE duplex testing
- decreased pulsatility and no reversed flow in late systole
- diastolic flow may or may not be seen
- blunted systolic component t
- common distal to hemodynamically significant stenosis or occlusion
what does a focal velocity increase of >/= double of the prox segment indicate
- hemodynamically significant lesion > 50%
what does a focal velocity increase of >/= triple of the prox segment indicate
- hemodynamically significant lesion of > 70%
what 4 other things indicate presence of stenosis
- spectral wave form changes
- post stenotic turbulence
- color aliasing
- color bruit
what are 3 indirect signs of stenosis when a proximal normal velocity cannot be obtained
- increased velocities with luminal reduction and post stenotic turbulence
- spectral waveform changes form one segment to next
- arterial wave form comparison at the same site in contralateral artery
what does a staccato wave form indicate
- severe distal stenosis or complete distal occlusion
what color parameter indicates a complete occlusion
- flow not detected by cold and spectral doppler in vessel
the presence of what vessel can help indicate occlusion extent
- large collateral at the pool and distal ends
what characteristics (waveform spectral broadening velocity and distal waveform) will a normal vessel present with
- triphasic
- none
- none
- normal
what characteristics (waveform spectral broadening velocity and distal waveform) will a vessel with 1-19% stenosis present with
- triphasic
- minimal
- < 30% increase in PSV from proximal segment
- normal prox and distal
what characteristics (waveform spectral broadening velocity and distal waveform) will a vessel with 20-49% stenosis present with
- tri/biphasic
- prominent
- 30-100% increase in PSV from prox segment
- normal prox and distal
what characteristics (waveform spectral broadening velocity and distal waveform) will a vessel with 50-99% stenosis present with
- monophasic
- extensive
- > 100% increase in PSV from prox segment
- waveform monophasic distal
what characteristics (waveform spectral broadening velocity and distal waveform) will a completely occluded vessel present with
- no flow (pre occlusive thump prox)
- none
- none
- collateral waveform monphasic with reduced PSV
what are 3 other correlative diagnostic tests
- CTA
- MRA
- arteriography
what are 5 medical treatments of peripheral arterial disease
- modify risk factors
- exercise routine
- anti-platelet medications
- anticoagulation
- thrombolysis
what are 5 surgical treatments of peripheral arterial disease
- bypass grafting
- artherectomy
- resection
- sympathectomy
- amputation
what are 3 Endovascular treatments of peripheral arterial disease
- angioplasty
- stent
- intraarterial directed thrombolysis